Perfluorochlorosulfenyl chlorides



United States Patent This application is a division of copending application Serial No. 48,361 filed August 9, 1960, now Patent No.

3,100,228, which is a continuation-in-part of copending application Serial No. 658,508, filed May 13, 1957, now abandoned.

This invention relates to certain new perfluorochloropolysulfides and to sulfenyl chlorides derived therefrom.

The compounds of the invention are oily materials or soft wax or grease-like materials characterized by low volatility and high chemical stability. Because of this combination of properties and of their lubricity, the compounds of the invention are useful as lubricants or as lubricant additives, such as in high pressure gear lubrication, and are also useful as cutting oils or cutting oil additives.

The perfluorochloropolysulfides of the invention are those of the general formula:

where R, is a perfluorochloroalkyl radical preferably having from 1 to 10, most desirably from about 2 to 6 carbon atoms. A perfluorochloroalkyl radical as used herein means an alkyl radical which contains only the elements carbon, chlorine and fluorine. The symbol X refers to an integer having a value ranging from 2 to about 5. It will be understood that the invention includes compounds where the two R radicals are the same or different. Preferably, the molar ratio of fluorine to chlorine in the perfluorochloroalkyl radical Rf is at least 1:1.

The perfluorochloropolysulfides of the invention may be prepared by reacting perfluorochloroalkyl iodides of the general formula:

where R, is as defined above, with elemental sulfur. The reaction of the iodide and the sulfur results in the liberation of elemental iodine and the linking together of two perfiuorochloroalkyl radicals between a chain of two or more sulfur atoms. The reaction to form a disulfide may be represented, for example as follows:

The reaction between the iodide and the elemental sulfur may be carried out at temperatures between about 150 C. and 300 C. and preferably between about 160 C. and 200 C. Reaction pressure is not a critical factor, and the reaction may in general be conducted between atmospheric pressure and higher pressures, e.g., up to 10,000 p.s.i.g. and higher. Time of reaction is again not critical and may be from a matter of say 10 minutes to several days. The proportion of sulfur used will depend to some extent on the amount of sulfur it is desired to have in the final product. Generally a molar excess of sulfur is desirable and usually between about 2 and 20 moles of elemental sulfur (S) will be present per mole of. iodide. 1

In carrying out the reaction any suitable technique may be employed. Conveniently, the ingredients are simply put into a suitable vessel, such as a stainless steel or Monel autoclave or a glass vessel, in an inert atmosphere, and

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heated to the required temperature with stirring. In certain cases, it may be desirable to use an inert solvent, such as a fluorochloroalkane, as the reaction medium. Alternatively, the reaction may be carried out by passing the reactants through a heated tube.

The perfluorochloroalkyl iodides starting materials for the reaction may be conveniently prepared, for example, by reacting a perfluoroalkyl, or a perfluorochloralkyl iodide with chlorotrifiuoroethylene, CF =CFCl, under free radical conditions to produce low molecular weight iodide telomers in accordance with procedures that are well known per se. Suitable starting iodides which may be used to prepare the perfluorochloropolysulfides of the invention include, for example,

In another aspect of the invention, the novel perfluorochloroalkylpolysulfides of the invention may be converted into novel sulfenyl chlorides by reaction of the polysulfides with elemental chlorine to produce sulfenyl chlorides having the general formula:

R CF CFClSCI where R, is as defined above.

The reaction of the perfiuorochloroalkylpolysulfides with chlorine to produce the above sulfenyl chlorides is preferably conducted at temperatures between about 20 C. and 250 C. usually between 50 C. and about C. Pressure is not critical and pressures ranging, e.g., from atmospheric, e.g., to 10,000 p.s.i.g. and higher may be used. Reaction time is likewise not critical and may range from say 10 minutes to several days. Chlorine is preferably use in molar excess, proportions ranging, e.g., from 1 to about 10 moles of chlorine (C1 per mole of polysulfide.

Again, the partcular manipulation technique by means of which the chlorination of the polysulfide is carried out is not important. Conveniently, the polysulfiide is put into a pressure vessel with the required amount of chlorine and heated to reaction temperature. Alternatively, the reaction can be carried out by passing the chlorine and polysulfide through a hot tube.

Typical sulfenyl chlorides of the invention include, for example:

The following examples are for the purpose of illustrating the invention.

Example 1 A heavy wall pyrex tube having a 100 milliliter capacity is charged with 1.92 g. (0.06 mole) of elemental sulfur and 12.36 g. (0.03 mole) of CF ClCCl CF CFClI under an atmosphere of dry nitrogen. The tube is heated in an oil bath at C. for 2 hours.

The reaction product, a viscous oil consisting of perfluorochloroalkylpolysulfides of the formula is separated from the liberated solid iodine and then distilled in a small Vigreaux distillation unit. Three fractions are collected:

(a) A fraction boiling at 166 to 167 C. at about 0.1 mm. Hg having a refractive index 11 1.4840, this being the disulfide.

Analysis.Calculated for: C, 15.16; Cl, 44.75. Found: C, 15.00; Cl, 44.64.

(b) A fraction having a boiling point of 167 to 182 C. at about 0.1 mm. Hg, and a refractive index 11 1.4995, this being the trisulfide Analysis.-Calculated for: C, 14.4; C1, 42.6; S, 14.4. Found: C, 14.2; C1, 42.5; S, 14.0.

(c) A heavy oil consisting of polysulfides of the formula where x is 4 to 5.

Fractions (a) and (b) are non-volatile oils having excellent lubricity useful particularly where extreme pressure lubricant characteristics are desired.

Example 2 A heavy wall pyrex tube is charged with 40 g. of the iodide CF ClCFClCF CFClI, and 12.8 g. (0.4 mole) of elemental sulfur. The tube is sealed under an atmosphere of nitrogen and then heated for 112 hours at 175 to 180 C. A viscous high boiling oil is obtained consisting of polysulfides of the formula CF CICF CICF CFClS -CFC1CF CFClCF C1 where x is mostly from 2 to 3.

Example 3 A heavy wall glass tube is charged with 51 g. (0.1 mole) of the iodide CF ClCFC1(CF CFCl) I and 12.8 g. (0.4 mole) of elemental sulfur. The tube is sealed under an atmosphere of dry nitrogen and then heated for 112 hours at 175 to 180 C. The product, a viscous oil, is removed from the tube, dissolved in methylene chloride and washed with sodium thiosulfate. After drying and solvent removal there is obtained 26 g. of a viscous high boiling oil comprising perfiuorochloropolysulfides of the formula:

where x is mostly from 2 to 3, and a residue of soft solids where x is 4 to 5.

Example 4 The iodide CF (CF CFCl) I is reacted with elemental sulfur following the procedures of the previous examples. There is obtained a viscous high boiling oil consisting of perfluorochloropolysulfides of the formula CF (CF CFCI) S CFClCF CF where x is mostly from 2 to 3.

Example 5 The perfluorochloropolysulfide prepared in accordance with Example 1 having the formula:

is chlorinated for one hour at 150 C. and then for onehalf hour at 200 C. by bubbling anhydrous chlorine 4 through the polysulfide in a glass tube. The chlorinated product is distilled in a small Vigreaux distillation unit at 20 mm. Hg. There is recovered a fraction boiling at to C. at 20 mm. Hg, this being the perfiuorochlorosulfenyl chloride of the formula:

In a similar manner, the perfiuorochloropolysulfide prepared in accordance with Example 1 of the formula is chlorinated to produce a sulfenyl chloride of the same formula given above.

Example 6 The perfluorochloropolysulfide prepared in accordance with Example 2 of the formula where x is mostly 2 to 3 is chlorinated at a temperature of from to 200 C. by passing elemental chlorine through the polysulfide for 2 hours. A sulfenyl chloride having the formula CF ClCFClCF CFClSCl is obtained in good yield.

Example 7 A polysulfide prepared in accordance with Example 3 of the formula where x is most 2 to 3 is chlorinated according to the procedures of the previous examples and a sulfenyl chloride of the formula CF CICFCKCF CFCD SCI is obtained.

Example 8 A perfiuorochloropolysulfide prepared in accordance with Example 4 of the formula is chlorinated in accordance with the procedures of the previous examples. There is obtained a perfiuorochlorosulfenyl chloride of the formula CF (CF CFCl) SCl.

The perfluorochloropolysulfides and sulfenyl chlorides of the invention are high boiling oily materials or waxy materials of relatively low melting point. These materials are useful as synthetic lubricants either in themselves or as anti-wear or extreme pressure additives for lubricants which are used, for example, in the lubrication of hypoid gears. The sulfenyl chlorides also have utility as fungicides.

It is to be understood that other variations and embodiments are included within the scope of the invention in addition to those specifically described above; the embodiments described are for the purpose of illustrating and exemplifying the invention and the invention is not limited thereto.

We claim:

1. Perfiuorochlorosulfenyl chlorides of the formula:

Where R is a prefluorochloroalkyl radical.

2. Perfluorochlorosulfenyl chlorides in accordance with claim 1 in which said perfluorochloroalkyl radical contains from 2 to 6 carbon atoms.

3. Perfluorochlorosulfenyl chloride of the formula:

References Cited by the Examiner UNITED STATES PATENTS 3,019,258 1/62 Hauptschein et al 260-543 LORRAINE A. WEINBERGER, Primary Examiner.

LEON ZITVER, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,211,787 October 12, 1965 Murray Hauptschein et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 53, for "-CFClCF R I read CFClCF R +I column 2, line 44, for "use" read used line 47, for "partcular" read particular column 4, line 60, for "prefluorochloroalkyl" read perfluorochloroalkyl Signed and sealed this 3rd day of May 1966.

iEAL) ttest:

KNEST W. SWIDER EDWARD J. BRENNER mating Officer Commissioner of Patents 

1. PERFLUOROCHLOROSULFENYL CHLORIDES OF THE FORMULA: 